Anyone Using Mastervolt AGM Batteries?

Ducky's Dad

Explorer
Since I am thinking seriously about replacing all three batteries in my truck (one Odyssey and two Optimas), I'm evaluating the alternatives. Was talking yesterday with a guy who installs and repairs marine electrical and electronic systems and he told me I should go with Mastervolt AGMs. They are a bit cheaper than Odyssey or Northstar, also lighter (less lead). and lower capacity than the other two, but this guy claims that the quality is an order of magnitude better than the competition. I have been averaging about three years on my last three Odyssey Grp 31s, and they will still start the truck but capacity is so compromised that there is relatively little leeway to drain the starting battery with lights or OBA or winching, even with the engine running. The Optimas have their hands full running the fridge in the desert, so might replace them just to get more amp hours.

Anyone have direct experience with Mastervolt?

https://www.mastervolt.com/products/agm-12v/
 

john61ct

Adventurer
No but Odyssey is widely known to be a top-notch AGM maker, as with Lifeline.

MasterVolt is likely relabeling another maker's, and while a quality brand, is rarely a better value - need to compare price per AH, but reputation is tge most important.

How long did you get? Where you coddling them?

AGM just don't last as long as FLA, and their charging requirements are much more demanding, easy to murder them early.

Do you actually **need** sealed?

Where are you located?
 

Ducky's Dad

Explorer
MasterVolt is likely relabeling another maker's, and while a quality brand, is rarely a better value - need to compare price per AH, but reputation is tge most important.
Mastervolt is not relabeling, made in Holland as I understand it. Marine electronics dealer in Seattle told me they are great, unless there is a problem, then it takes forever to resolve or replace. He recommended Lifeline, evn though he is a Mastervolt dealer.

How long did you get? Where you coddling them?
Averaging about three years each on the Odyssey G31s. First one developed a dead cell right at the three year mark. Second one failed to take a charge at about three+ years. Third one is in the truck now, will be three years old next month. Won't take a full charge, won't hold a charge for more than a couple of weeks. No measurable parasitic drain, beyond spec. First Odyssey was not coddled, just plug and play. Second one treated respectfully, run on conditioning cycles periodically with 40amp Odyssey smart charger. Third (current) one has been coddled, started with conditioning charges every month on Odyssey 40amp charger, then progressed to frequent conditioning charges on new Odyssey 20amp smart charger, now gets a full conditioning charge every week or two, will not take a full charge. For the first year or so, I kept a detailed log of SOC, charge cycles, dates and miles driven, etc. After the first couple of months, battery would not get to or hold a full charge at 12.86 resting OCV, all in the log. Decided logging all this data was a waste of time.

AGM just don't last as long as FLA, and their charging requirements are much more demanding, easy to murder them early.
Have had numerous phone calls with Odyssey tech support and I am doing everything by the book. No murdering going on here.

Do you actually **need** sealed?
I actually need high capacity for the starting battery, and need AGM for the house batteries because they are mounted on their sides under the truck. Lithium ion is not an option because this is mostly a desert truck and they don't like the heat.

Where are you located?
I'm in So Cal, not all that far from the Lifeline factory. Lifeline is not answering their phones today. Lifelines appear to be dual purpose AGMs, but with better ah and worse cca than Odyssey or Northstar.
 

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john61ct

Adventurer
Find a local Lifeline or Northstar if you're tired of Odyssey, but all three are definitely great quality.

Ignore CCA, G24-31 will have plenty of cranking power.

With great care protocols and the right gear, you might get to 5-7 years, but with a small bank probably cheaper to just do the best you can and replace every 3-4.

Consider creating one big Main / House bank, then a high-amp adjustable LVD to isolate the "Starter / Reserve cell" from the rest as SoC drops.

Big fat wires in between, that's the hard / pricey part.

Keep a little lithium jumpstarter pack charged up for belt & suspenders.
 

john61ct

Adventurer
this is mostly a desert truck and they don't like the heat.
Heat kills lead just as bad, that could easily be your issue.

If you consider my "one big bank" design, put them all together under the chassis, I'm sure you'll find a use for the empty space in the engine compartment at some point.
 

john61ct

Adventurer
Re care protocol for the House bank, if you're looking to improve longevity:

Are you doing your 20-40A charging off grid mains overnight, or from a genny while boondocking?

Any solar for the long tail?

What BM are (were) you using to guesstimate SoC?

Have you got an ammeter wired in to measure live current levels in and out the bank.
 

Ducky's Dad

Explorer
Heat kills lead just as bad, that could easily be your issue.
True, but it seems to kill lithium ion faster than lead acid.

If you consider my "one big bank" design, put them all together under the chassis,
Don't really need to physically move them in the truck, because I can switch them as one big bank with the current setup. The house batteries are already under the cab, but they are a pair of 34s because there is so much crap under there already (skid plates and such) that those were the biggest boxes I could fit. Also, I had some 34s left over from another project. Trying now to figure whether I could tweak the boxes to take a pair of G24s, which could add about 42ah to the bank over the current setup.

Are you doing your 20-40A charging off grid mains overnight, or from a genny while boondocking?
Conditioning charges are always off mains power. On the road I have a 270 amp alternator that can dump as much current into the bank as it will take, with about 115 amps produced at idle. Can't change the charge profile because the voltage regulator is in the ECU and can't be reprogrammed, even by a dealer. Dealer techs tell me that an external regulator is not a smart idea. My computer is already a little confused.

Any solar for the long tail?
Have a Renogy 100W panel sitting in the box, ready to install when I get the new roof rack onto the truck. Current rack is full and overloaded. Have not decided on a controller yet.

What BM are (were) you using to guesstimate SoC?
Using a couple of multimeters and the SOC tables from Odyssey tech support.

Have you got an ammeter wired in to measure live current levels in and out the bank.
My 40amp/3-bank Odyssey charger has a setting that displays amps in during the conditioning charge. Nothing yet for realtime monitoring on the road.
 

john61ct

Adventurer
Can't change the charge profile because the voltage regulator is in the ECU and can't be reprogrammed, even by a dealer.
Sterling BB series DCDC charger, I believe 120A is currently the biggest, but Charles has 180A and maybe 240A units in the pipeline.

No problem with even Euro style brake regen system vehicles that usually can't charge a batt out of a paper bag.

Get a V/A shunt-based display from House mounted at the dash, maybe $50-60.

SmartGauge for SoC, but only if "the House bank" is a stable entity. Nothing is real accurate, but SG pretty close and much more user-friendly.

You don't want any "lithium" but LFP, and at 5-7x the price per usable AH, need really precise charging - like the Sterling above - before even thinking about it, and yes heat will mean shorter lifespan even if all the other care parameters are perfect.
 

Ducky's Dad

Explorer
Sterling BB series DCDC charger, I believe 120A is currently the biggest, but Charles has 180A and maybe 240A units in the pipeline.
Yes, last time I looked into DC/DC chargers I found nothing suitable. But things change.

Odyssey has told me several times that regular conditioning on an appropriate smart charger will prolong the life of their batteries, up to maybe nine years. That does not seem to be the case here. Mine came off the Odyssey charger this morning after three full cycles (with cooling/resting periods in between) at 12.4V, and that was even before the surface charge had dissipated. Full charge is specified at 12.86V or higher. I can't even get close to that. The battery is now on a cycle with the little (7 amp) Ctek 7002, just to see if that gives any better results. My Optimas seem to prefer the Ctek, but that is an observation rather than a documented fact at this point.
 

john61ct

Adventurer
Odyssey has told me several times that regular conditioning on an appropriate smart charger will prolong the life of their batteries, up to maybe nine years. That does not seem to be the case here.
Actually Lifeline's the only quality AGM maker in NA that still recommends equalizing / conditioning.

But even for FLA, that's just one small piece of the puzzle.

A high charge rate .2-.4C at least for the first hour or so is healthy for AGM.

Not dropping from Absorb until endAmps, not drawing too often below 50% SoC are important

And of course your unavoidable high temp issue.

Here's a good summary: http://www.cruisersforum.com/forums/f14/lifeline-battery-problems-better-brands-186904.html#post2421951

_____
Odyssey is not known for good chargers, but I dunno.


Mine came off the Odyssey charger this morning after three full cycles (with cooling/resting periods in between) at 12.4V

Yes they're toast, if the charger is configured and operating properly.

But voltage is not a good indicator of 100% SoC, should use an ammeter.

Optima is just for cranking right? Not paralleled to House?
 

DiploStrat

Expedition Leader
To expand on the points in the link above, if you read nothing else, read the Lifeline Technical Manual. You should even read the advertising part.

Note carefully the sections on:

-- Sizing
-- Wiring
-- Discharging
-- Charging. (Lifeline calls for up to 5C charging, for most of us, that is simply impossible!)


Finally, the one quote that Lifeline gave me: most batteries die because they are never fully recharged. As much as I preach the benefits of alternator charging, the fact remains that most of us won't ever get to a true 100% charge without solar or shore power.

http://2cw8eb1vmmgg3g5i7jzt6upo.wpengine.netdna-cdn.com/wp-content/uploads/2015/12/6-0101-Rev-E-Lifeline-Technical-Manual.pdf

I actually worry a bit about my present setup as I have only 40A available from the alternator because of the size limitations of my B2B. So far, with over 600w of solar and a few hours drive every other day or so, I have not had a problem. And that is why I believe that some kind of decent SOC meter, not just a voltmeter, is essential. As the folks at Bogart put it, even the best speedometer cannot substitute for a gas gauge. ;-)
 
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Ducky's Dad

Explorer
Actually Lifeline's the only quality AGM maker in NA that still recommends equalizing / conditioning.
Well, actually, two different people at Odyssey have told me that I MUST run conditioning charges on my G31 to keep it happy. One was Kathy in tech support and the other was some guy in senior management whose name I have somewhere in my notes. They were adamant that these batteries must be conditioned periodically. Got the same thing from a guy in their charger department, so that's three Odyssey peeps who have told me to condition the battery.

A high charge rate .2-.4C at least for the first hour or so is healthy for AGM.
Not dropping from Absorb until endAmps, not drawing too often below 50% SoC are important...
Odyssey is not known for good chargers, but I dunno.

I have three Odyssey-branded chargers from two different manufacturers. One is the Schumacher-built 40amp three-bank with some user-settable controls. The other two are the new 20amp units from an unknown manufacturer, plug&play with no user settings (idiot proof?). All three are Odyssey-branded smart chargers, supposedly designed and optimized specifically for Odyssey batteries. All three were obtained NIB, directly from Odyssey. All three give the same results. I also have two Ctek 7002 smart chargers, current manufacture, with AGM and Recondition settings. Virtually the same results as the Odyssey chargers. And I have an Optimate AGM smart charger that works just fine on my old, semi-retired Optima and Odyssey G34s, but works the same as the others on the G31. And then there's the old Craftsman and Schumacher dumb chargers which I keep around because they can jump start a dead vehicle. The current G31 has only been below 50% SOC a few times in three years, and has immediately gone on conditioning cycles.

Optima is just for cranking right? Not paralleled to House?
Optimas are the house batteries. Odyssey is the starting battery. I can set them to parallel if I choose, but they are always parallel when I want to charge the Optimas from the alternator. Isolated when off, unless I set them otherwise.

This battery BS is starting to irritate me. Best price I can find on three Northstars to replace the current batteries is over $1K. I just bought new batteries 35 months ago. Did not find anything on the Lifeline website that would be a good physical fit for my house battery boxes, and they never called me back on Friday. Will try to have a live conversation with them next week.

Did have a phone call with Edge programmers on Friday to see if the CTS/Insight Programmer/gauge pod could be draining the battery when truck is idle. Turns out they had a problem with that on the early versions of my programmer, but they swear that my version does not have that issue. So I'm going to unplug it from the OBD-II port tomorrow and see what happens.
 

john61ct

Adventurer
most batteries die because they are never fully recharged. As much as I preach the benefits of alternator charging, the fact remains that most of us won't ever get to a true 100% charge without solar or shore power

And that is why I believe that some kind of decent SOC meter, not just a voltmeter, is essential.
An ammeter will do at the top end, ensure endAmps is reached at Absorb most cycles before dropping to Float.

> I actually worry a bit about my present setup as I have only 40A available from the alternator because of the size limitations of my B2B.

The high charge rate is good for longevity but not as critical as the SoC top and bottom.

Go direct off the alt for the first few hours of driving sometimes?

Or save your pennies and trade up to Sterling's 120A if you think it's worth it.
 

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john61ct

Adventurer
Yes it's a frustrating topic.

Optima sucks for deep cycling, very poor value due to short lifespan since Odyssey the spiral inventor spun it off to JCI. Solid for cranking though.

Odyssey is great for both, but maybe used as a Starter or other aspect of your care profile is why they recommend equalizing. Do you have a link to the specific model, and maybe the protocol / profile spec?

My reco chargers are Magnum, Sterling Power ProCharge Ultra and ProMariner Pronautic P. Higher amps the better, can always be de-rated for sub par mains or a small genny.

If you stop Absorb only after hitting endAmps spec, most cycles, avoiding PSOC, then no need for equalizing, you should get many years from any of the three mfg.

G31, oversized a bit for variations is a good size box if you need to mod.

An ammeter is basic, verify yourself about parasite drains.

You can't really know how often you're getting to 100% Full without one. 99% is not close to 100% wrt longevity.

And same with the 50% bottom point, without counting AH down from known-Full.
 

DaveInDenver

Expedition Leader
I forget who now, but I think someone else was experiencing exceptionally short lives with G31 Odysseys. I have a G25 and G35 pair that seem to be holding up pretty well. I wonder if G31 is a particular issue with Odyssey.
 
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